Fionn O Briain

Fionn O Briain was a Sinn Fein TD. O Briain was an opponent of the 1921 Anglo-Irish Treaty and a supporter of Eamon de Valera, and he was one of the deputies who walked out of the Dail Eireann to protest the ratification of the treaty. O Briain later joined the Fianna Fail party due to his support for De Valera.